Also known as Accuracy, Bias is an estimate of the error in the measurement system. Bias is estimated by taking repeat samples of a part or standard using the measurement system, and comparing the average of these measurements with a measurement taken of the same piece using equipment with higher accuracy.
BIAS = Average of Measurements – Reference Value
% Bias = (Bias / Process Variation) * 100%
PV is the Process Variation, which may be estimated as 6 times the Process Sigma value calculated from a control chart.
Learn more about the DOE tools for designed experiments in Six Sigma Demystified (2011, McGraw-Hill) by Paul Keller, in his LSS Black Belt Course.
Learn more about the Statistical Inference tools for understanding statistics in Six Sigma Demystified (2011, McGraw-Hill) by Paul Keller, in his online Black Belt certification training course ($875).
Learn more about the Regression tools in Six Sigma Demystified (2011, McGraw-Hill) by Paul Keller, in his online Black Belt certification training course ($875).
Learn more about the Quality Management tools for process excellence in The Handbook for Quality Management (2013, McGraw-Hill) by Paul Keller and Thomas Pyzdek or their online Quality Management Study Guide.
Learn more about the Quality Improvement principles and tools for process excellence in Six Sigma Demystified (2011, McGraw-Hill) by Paul Keller, or his online Green Belt certification course ($499).
Learn more about the Lean Six Sigma principles and tools for process excellence in Six Sigma Demystified (2011, McGraw-Hill) by Paul Keller, in his online Green Belt certification course ($499).
Learn more about the SPC principles and tools for process improvement in Statistical Process Control Demystified (2011, McGraw-Hill) by Paul Keller, in his online SPC certification course ($350) or online Green Belt certification course ($499).